As generally known, a double boiler for domestic use is an appliance in which several kinds of medical stuff or other food are boiled down together with water by means of power for a predetermined time.
FIG. 1 is an exploded perspective of a prior art double boiler. As depicted in the drawing, double boiler for domestic use 10 comprises a main body 12 incorporated internally with several electrical components (not shown) such as heater, a heating vessel 14 made of glass and detachably mounted on the top of main body 12, a handle 16 installed on the outer surface of heating vessel 14, a filtering device 18 mounted on the inner surface of heating vessel 14 for containing various kinds of medical stuff, and a steam condenser 19 provided above heating vessel 14 for condensing the steam generated therefrom and thus collecting it into heating vessel 14.
The conventional double boiler constructed as above is, however, very inconvenient in that the steam condenser is manually joined with the heating vessel and disjoined therefrom after the decoction of medical stuff (in particular, Oriental medicines).
In addition, the steam containing components of medical stuff gathered in the steam condenser cannot be quickly cooled and withdrawn into the heating vessel during the process of decoction. The steam is unfortunately externally discharged so that the medical stuff components are lost. The steam leaked could make people feel uncomfortable when it spreads indoors.
For those reasons, there has been suggested a deducting device in which a blower is installed above the steam condenser. This conventional structure is shown in FIG. 2. As in FIG. 2, the double boiler consists of a main body 20 having several electrical components (not shown) thereinside, a frame 22 to which main body 20 is supported, a heating vessel 24 made of glass and detachably mounted on the top of main body 20, an inner container 26 mounted on the inner surface of heating vessel 24 for receiving various kinds of medical stuff, a steam condenser 28 provided above heating vessel 24 so that the steam produced from heating vessel 24 is liquefied and thus collected thereinto, and a cooling fan 30 installed to frame 22 for cooling steam condenser 28.
This double boiler is effective in rapidly cooling steam, compared with that shown in FIG. 1. However, it is still inconvenient that the heating vessel and steam condenser should be manually joined or disjoined. In addition, the steam condenser is externally exposed so that the user may be unfortunately burned because of carelessness.